AT&T has almost another $5 billion to pursue expansion in Europe now that it has agreed to sell or lease 9,700 cell towers to independent operator Crown Castle International.

The $4.85 billion deal, which is expected to close before the year is out, would essentially double AT&T's cash on hand. Crown Castle is buying 600 of the towers outright and will get to lease and operate the remaining 9,100 for the next 28 years, on average.

"Withthe transaction, Crown Castle will not only reclaim the position of largest tower operator in the U.S, but also takes control of a large-scale, high-quality asset portfolio with attractive growth potential at a time when demand for U.S. wireless infrastructure kicks into high gear," said Canaccord Genuity analyst Greg Miller.

It's widely anticipated that, with the U.S. government reluctant to approve a huge acquisition by AT&T in the States – recall the failed T-Mobile takeover – that AT&T could be on the verge of buying a major operator across the pond. This cash infusion could go a long way toward making that happen.